Tee power divider and combiner based negative group delay topology.

An innovative topology of negative group delay (NGD) microwave circuit based on the interconnected power divider and combiner (PWD/PWC) is investigated. The distributed cell consists of PWD and PWC with the input and outputs interconnected by a transmission line (TL). The theory is based on the S‐parameter modeling. The NGD existence condition is formulated. The NGD properties constituted by the NGD bandwidth, level and figure of merit are introduced. It is shown that the distributed topology behaves as a bandpass NGD circuit. The NGD topology theoretical efficiency is verified with simulations by considering NGD circuit parametric analyses by varying the PWD‐PWC interconnect TL attenuation. To validate experimentally the NGD concept, two prototypes of one‐ and two‐stage passive NGD cells were designed in microstrip technology, fabricated and tested. The one‐ and two‐stage circuit prototypes exhibit NGDs of about −2.2 ns and −4.7 ns with −3.4 dB and −7.5 dB insertion loss, respectively. The NGD phenomenon was generated around 1.85 GHz‐center frequency over about 35 MHz‐NGD bandwidth. [ABSTRACT FROM AUTHOR]